An x-ray system includes a filament that operates as a cathode to emit electrons to an anode target. The filament is heated by application or supply of an electrical current through or to the filament. This current results in electrons being stimulated and ejected from the filament and received at the anode target. When a high voltage is applied between the cathode and the anode, the electrons are accelerated toward the anode target. The electrons that strike the anode target result in x-rays being produced in a manner that is proportional to the current flowing to the filament.
Each x-ray tube of a device that emits x-rays may have several emitters, but each tube may only emit electrons from a single emitter at a time. For example, while one emitter is emitting electrons, the remaining emitters are not active or are not emitting electrons. In order to control the electrons emitted from an emitter, the current from the x-ray emitter that is emitting electrons is measured. This current is measured between the cathode and anode of the emitter, and may only be measured at low voltage potentials (such as potentials that are less than 40 kilovolts (kV)) in some known devices.
The current from the x-ray emitter or emitters in some known x-ray systems are measured collectively. For example, the overall tube current may only be able to measure the total current from the emitters and may not be capable of separately measuring the current from each individual emitter. As a result, the power supplies for known x-ray systems having multiple emitters are unable to control the x-ray emissions from each emitter separately.